A loop of wire lies flat on the horizontal surface in an area with uniform magnetic field directed vertically up. The loop of wire suddenly contracts to half of its initial diameter. As viewed from above induced electric current in the loop is:

To oppose applied magnetic field current will flow in anticlockwise direction

Explanation:

Given:

Uniform magnetic field directed vertically upward.

Current will flow in clockwise direction

Here loop of wire is suddenly contracts to half so diameter of loop is reduced.

Hence less number of magnetic field line pass through the loop. This change in magnetic field lines lead to flow of current.

Now from lenz law flow of induced current will oppose the cause of its production

Therefore, to oppose applied magnetic field current will flow in anticlockwise direction.

a.   mass number from atomic number

magnets not strong enough

explanation: